Investigations into Performance of Minimally Invasive Telesurgery with Feedback Time Delays

Abstract

This paper describes the testbed telesurgery system that was developed in MIT's Human Machine Systems Laboratory. This system was used to investigate the effects of communication time delays on controller stability and on the performance of surgical tasks. The system includes a bilateral force-reflecting teleoperator system, interchangeable surgical tools, audio and video communication between the master and slave sites, and methods to generate time delays between the sites. To compensate for the time delays, various control schemes were investigated, leading to the development and selection of fuzzy sliding control (FSC). With a stable teleoperator system, experiments in performing a variety of surgical exercises were conducted. These looked at the performance of a team of a telesurgeon and local assistant given a number of different time-delay scenarios, including synchronous and asynchronous force and audio/video feedback. The results of the research project include the development of the novel FSC algorithm, data on how time delays degrade performance of surgical tasks, and recommendations on how telesurgery should be performed to accommodate telecommunication time delays.

Effects of Experience and Workplace Culture in Human-Robot Team Interaction in Robotic Surgery: A Case Study

“…In addition to the necessary coordination related to preparing the robot and specialized instruments, maintaining patient status, and ensuring a smooth flow of the procedure, the remote teams must also coordinate their activities, often with a time lag due to transmission bandwidth limitation [33]. Delays in feedback have been shown to adversely affect the performance and coordination of remote manipulation tasks and communication [34]. Research has suggested that more effective training and evaluation methods, along with a focus on teamwork and communication, may mitigate some of the risks of patient harm in robotic surgery [35][36][37].…”

Modeling the effects of delayed haptic and visual feedback in a collaborative virtual environment

“…An early study by Ferrell [1966] showed that, as with visual feedback, delayed haptic feedback in a positioning task results in an increase in performance time and errors, but the intervals of delay (0.3, 1, 3 s) were not sufficiently small that we can learn about how the user might respond to subtle increases in latency. A study of latency in tele-surgery [Ottensmeyer et al 2000] demonstrated that surgeons are more sensitive to a latency in haptic feedback than in visual when performing a laparoscopy task. However, the levels of latency examined (600 or 1200 ms) were again too large, as well as too few in number, to provide a model of performance.…”

Generic Control Interface for Networked Haptic Virtual Environments

“…While the low level layer provides a consistent, low latency infrastructure for buffering messages to and from multiple remote locations, the higher level layer [9] builds on top of this to provide a hierarchical topology for Distributed Virtual Environments (DVEs). This topology assumes that the environment is split into domains and controls the individual users in these domains.…”

“…The users experience and sense of immersion would be enhanced and would complement the visual display only if both the haptic and the visual feedback are consistent with each other. Evidence show that latency is a limiting factor in shared haptic environments [9]. Latency creates a lag from when collision is detected and when a force is applied to the display device.…”